import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Scanner;

/**
 * \* Created with IntelliJ IDEA.
 * \* User: Administrator
 * \* Date: 2021/12/3
 * \* Time: 14:46
 * \* To change this template use File | Settings | File Templates.
 * \* Description:
 * \
 */
class Studen{
    private String name;
    private String classes;
    private double score;

    public Studen(String name, String classes, double score) {
        this.name = name;
        this.classes = classes;
        this.score = score;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getClasses() {
        return classes;
    }

    public void setClasses(String classes) {
        this.classes = classes;
    }

    public double getScore() {
        return score;
    }

    public void setScore(double score) {
        this.score = score;
    }

    @Override
    public String toString() {
        return "Studen{" +
                "name='" + name + '\'' +
                ", classes='" + classes + '\'' +
                ", score=" + score +
                '}';
    }
}

public class TestDemo {

    public static void main(String[] args) {
        String str1="welcome to bit";
        String str2="come";
        ArrayList <Character >list=new ArrayList<>();
        for(int i=0;i<str1.length();i++){
            char ch=str1.charAt(i);
            if(!str2.contains(ch+"")){//如果str2里面不包含ch
                list.add(ch);
            }
        }
        for (char ch:list){
            System.out.print(ch);
        }
    }

    public static void main2(String[] args) {
        ArrayList<Integer> integers=new ArrayList<>();
        integers.add(11);
        integers.add(2);
        integers.add(3);
        Collections.sort(integers);
        System.out.println(integers);
        Collections.reverse(integers);
        System.out.println(integers);
    }

    public static void main1(String[] args) {
        ArrayList<Studen >studens=new ArrayList<>();
        studens.add(new Studen("bit","102-2",99.3));

        System.out.println(studens);
    }

}
